Acetylene-dicarboxylic acid esters

Henry et al. 95) found that a normal addition of the azide group to acetylene dicarboxylic acid ester formed the Pb—N bond. 

Reactions of sulfonium cyclopentadienylids a,/ -Ethylene- from acetylene-dicarboxylic acid esters... 

Acetylene dicarboxylic acid esters react analogously [446]. Methyl buty-nene reacts at 80 °C and a pressure of 700 atm in the presence of bis-tri-phenylphosphine palladium-(Il)-chloride to give 1.2-dimethyl propene-(l)-dicarboxylic acid-(1,3) diethyl ester [448],... 

Diels-Reese reaction—Acetylene dicarboxylic acid ester syntheses s. 12, 727... 

Pyrazoles 25 were prepared with reasonable yields from preabsorbed on molecular sieves 3-phenylsydnone and acetylene dicarboxylic acid esters using supercritical CO2 as a medium (Scheme 15) [32],... 

Only the 1-benzyl-vic-triazole, crysts(from eth at 20°), mp 61°, appears to have been prepd and reported in the literature. Curtius Raschig(Ref 2) prepd 1-benzyl-vic-triazole by the reaction of benzyl azide with the methyl ester of acetylene-dicarboxylic acid, followed by sapon and decarboxylation. Wiley et al(Ref 3) prepd the compd directly and in better yield from acetylenedicar-boxylic acid, followed by decarboxylation to 1 -benzyl-vic-triaZole(77% yield)... 

C6H404)t Acetylene dicarboxylic acid dimethyl ester 600 g, 238... 

The reduction of acetylene dicarboxylic acid (or its monoethyl ester) leads to an interesting hydrodimerization reaction (Scheme 6). 

The most obvious route to vinyl azide synthesis lies in the addition of hydrazoic acid to an alkyne. Unfortunately, this reaction has been found to be successful with only one group of compounds, the esters of acetylene dicarboxylic acid (equation 1). Acetylene mono-... 

The thermal addition of alkynes to the C=S bond has been studied independently by groups headed by Behringer190191 McKinnon,192 194 Vialle,195 198 and Leaver.199-200 All have observed that the reaction between l,2-dithiole-3-thiones (7) and activated acetylenes such as aryl substituted alkynes and acetylene mono- and dicarboxylic acid esters gives rise to a mixture of 2-thioacylmethylene-l,3-dithioles (135) and l,6,6a/4-trithiapen-talenes (136). 

Selenourea and 1-aryl and 1,3-diaryIselenoureas reacted with acetylene-dicarboxylic acid and its dimethyl ester to give 3,4-dihydro-2-imino-2/f-l,3-selenazin-4-one-6-carboxylic acid derivatives, e.g., 220 and 221. The structure of 221 was deduced from that of its hydrogenation product 222. ... 

Aminobenzenethiol reacts with acetylenes and olefins to give 1,4-benzothiazines. Reaction with acetylene dicarboxylic acid and esters gives the 2-alkylidene derivates (35).79,80... 

In polar solvents, thebaine has been found to react with esters of propiolic and acetylene-dicarboxylic acids to give the bases (104 R = and (104 R = CO Me), and in methanol the... 

Esters of acetylene dicarboxylic acids RO2C—C=C CO2R... 

Elving and co-workers [39, 40] investigated the polarographic behavior of mono- anddibromosubstituted maleic andfumaric acids and their esters. Monobromomaleic acid is reduced to maleic, fumaric, and butadiene-1,2,3,4-tetracarboxylic acid, where the proportions of the products depend on the pH value. Monobromofumaric acid is reduced to fumaric acid. The esters of both acids are reduced to the esters of unsubstituted fumaric acid. Dibromomaleic and dibromofumaric acids and their esters are reduced to acetylene-dicarboxylic acid, and the half-wave potentials of the cis acid and its diethyl ester are less negative (by 0.04-0.18 and 0.10-0.12 V, respectively, depending on the pH value) than the half-wave potentials of the trans compounds. 

Diazopropyne reacts similarly with a monosubstituted acetylene to form 3(5)-alkynylpyrazoles (68LA113). Thus, the reaction of diazopropyne with acetylene-carboxylic acid methyl ether results in 5-ethynyl-l//-pyrazole-3-carboxylic acid methyl ether in 48 h in 62% yield. 5-Ethynyl-l//-pyrazole-3,4-dicarboxylic acid dimethyl ester was prepared by reaction of diazopropyne with acetylenedicar-boxylic acid methyl ether (Scheme 10). 

The course of the reaction does not change, giving products 2, when esters of acetylene mono-carboxylic or dicarboxylic acid are used as the dienophilc.14,126... 

Triphenylphosphine gives Michael additions to the activated triple bond of acetylene dicarboxylic esters in presence of acidic compounds HY (Scheme 1). The reactions take place easily at room temperature, even at -10°C [1], through formation of intermediate activated vinylic phosphonium salts, which undergo a subsequent Michael addition of HY. The reactions afford various stabilized ylides which can be isolated in high yields or undergo possibly evolution, for example by intramolecular Wittig reaction [2]. 

Acrylic acid [79-10-7] - [AIR POLLUTION] (Vol 1) - [ALDEHYDES] (Vol 1) - [ALLYL ALCOHOL AND MONOALLYL DERIVATIVES] (Vol 2) - [MALEIC ANHYDRIDE, MALEIC ACID AND FUMARIC ACID] (Vol 15) - [POLYESTERS, UNSATURATED] (Vol 19) - [FLOCCULATING AGENTS] (Vol 11) - [CARBOXYLICACIDS - SURVEY] (Vol 5) -from acetylene [ACETYLENE-DERIVED CHEMICALS] (Vol 1) -from acrolein [ACROLEIN AND DERIVATIVES] (Vol 1) -acrylic esters from [ACRYLIC ESTER P OLYMERS - SURVEY] (Vol 1) -from carbon monoxide [CARBON MONOXIDE] (Vol 5) -C-21 dicarboxylic acids from piCARBOXYLIC ACIDS] (Vol 8) -decomposition product [MAT. ETC ANHYDRIDE, MALEIC ACID AND FUMARIC ACID] (Vol 15) -economic data [CARBOXYLIC ACIDS - ECONOMIC ASPECTS] (Vol 5) -ethylene copolymers [IONOMERS] (Vol 14) -in floor polishes [POLISHES] (Vol 19) -in manufacture of ion-exchange resins [ION EXCHANGE] (V ol 14) -in methacrylate copolymers [METHACRYLIC POLYMERS] (Vol 16) -in papermaking [PAPERMAKING ADDITIVES] (Vol 18)... 

As for the unsaturated carbonyl compounds, the most significant groups are the oc,/ -unsaturated acids or esters. Some of their methods of formation are closely analogous, for example, (a) the Horner-Emmons or Wadsworth-Emmons reaction, and (b) the aldol-type reactions. Rather more specific methods are considered below for the formation of a,/ -acetylenic acids, and for the conversion of the unsaturated dicarboxylic acid, maleic acid, into its anhydride or into fumaric acid. 

The amino benzopyran of step 5 (2.0 g) and dimethyl acetylene dicarboxylate (1.24 g 1.01 ml) were refluxed in ethanol (30 ml) for 26 hours. The reaction mixture was cooled to 0°C and the insoluble yellow-brown solid was collected by filtration and washed with a little ethanol and dried to give 2.0 g of a product which was a mixture of maleic and fumaric esters obtained by Michael addition of the amine to the acetylene. This mixture of esters (2.0 g) was treated with polyphosphoric acid (30 ml) and heated on the steam bath with stirring for 20 minutes. The reaction mixture was then poured onto ice and stirred with ethyl acetate. The organic layer was separated, washed with water and dried. The solvent was evaporated to leave 1.6 g of a yellow orange solid. Recrystallisation of this solid from ethyl acetate gave the required product as fluffy orange needles, mp 187°-188°C. 

---